1. Field of the Invention
This invention relates in general to farm machinery. In particular, the invention relates to machinery for chopping crop residue left after harvesting.
2. Description of the Prior Art
After a crop, such as corn or wheat, has been harvested, a certain amount of crop residue, consisting of corn stalks, wheat stubble, or the like, is left behind. Prudent farming techniques and government regulations require that the crop residue be chopped into small pieces, and that a large amount of the chopped residue be left lying on top of the ground. This action prepares the soil for the next crop and helps to minimize soil erosion and pollution of air and water.
Prior art choppers include rolling choppers for chopping the crop residue in a direction perpendicular to the direction of travel. Other choppers have colters to chop the crop residue in a direction parallel to the direction of travel. The disadvantages to both of these types of machines is that the residue may lie in a particular orientation that causes the residue to be missed by the prior art chopper.
U.S. Pat. No. 4,884,391, issued Dec. 5, 1989, to Cosson, discloses a stalk cutting apparatus that has both a cutter wheel for cutting the stalks perpendicular to the direction of travel, and colters for cutting the stalks parallel to the direction of travel. The cutting wheel is mounted on one axle, and the colters are mounted on several axles located behind the cutting wheel. Thus, as the apparatus is pulled across a field, the crop residue is first chopped perpendicular to the direction of travel, and then parallel to the direction of travel.